Relativistic Electron Beam Propagation in High-Pressure Gases

Abstract

Experimental results are reported for the transport characteristics of relativistic electron beams in high-pressure atomic and molecular gases. Experimental results obtained with two different accelerators (ν/γ ∼ 0.05 and 1) are reported. It was found that the highest pressure at which efficient transport occurred was determined by two different physical processes for the two different intensity electron beams. The lower-intensity beam propagated efficiently throughout a large pressure range, and was attenuated at high pressure by Coulomb scattering of the beam electrons in the screened Coulomb field of the nuclei of the background gas atoms. The more intense electron beam was attenuated at a gas pressure which varied with different gases approximately inversely with the high-energy ionization cross section. A radial breakdown mechanism is proposed which may explain the loss process of the intense electron beam.